The poping sound is basically a backfire by the engine , which is nothing to worry about. If you've noticed, this same poping sound is quite louder on superbikes when they decelerate or rev match ...
Tvs engein is relaiable and also durable.I have riden 11500kms on 160 4v and I haven't faced any sound from any disc breaks (front or rear).and also head light is also good, it gives good lighting at ...